Yes. Uncorrelated with itself, i.e. Price(today) has no correlation to Price(yesterday). Then you'll get the 75% mean reversion probability.

You can prove this with a simple geometrical consideration. Suppose you have a set of today's prices Pt, and a set of yesterday's price Py. By definition, half the prices from Pt are below the median and half are above the median; same for Py. Now combine the two sets to a 2 dimensional set of vectors with coordinates (Pt,Py). Every such vector represents a possible price change from Py yesterday to Pt today. This set of price changes can then be split by the median lines into 4 sub-sets:

1. (Pt < Median, Py < Median)
2. (Pt < Median, Py > Median)
3. (Pt > Median, Py < Median)
4. (Pt > Median, Py > Median)

The 4 subsets have exactly the same number of elements when Pt and Py are uncorrelated. The value of the median does not matter.

Now, mean reversion, or more precisely moving in direction to the median value means the following condition:

(Pt > Py and Py < Median) // yesterdays Price was below the median and rises, i.e. todays price is higher
or
(Pt < Py and Py > Median) // yesterdays Price was above the median and falls


The first condition is fulfilled in half of subset 1 (the other half had Pt < Py) and in the full subset 3 (because Pt > Py always in subset 3). So, this happens for 1/2*1/4 + 1/4 = 3/8 of all elements.

The second condition is fulfilled in half of subset 4 (the other half had Pt > Py) and in the full subset 2 (because Pt < Py always in subset 2). This is true for another 3/8 of all elements.

3/8 + 3/8 = 6/8 = 75%.